This is a blog detailing the creation/evolution/ID controversy and assorted palaeontological news. I will post news here with running commentary.

Friday, December 02, 2011

Modern Humans Out of Africa Earlier Than Thought?

The Australian is reporting on the find in Arabia of stone tools purported to be crafted to modern humans that date to around 100 000 years ago (date derived by thermoluminescence). They write:

Jeffrey Rose, an archaeologist with Britain's Birmingham University and head of the Dhofar Archaeological Project, said: "After a decade of searching in southern Arabia for some clue that might help us understand early human expansion, at long last we've found the smoking gun of their exit from Africa."

The discovery also challenges current thinking about the route the migrants took, say Dr Rose and his colleagues, including geochronologist Bert Roberts of Wollongong University.

The article shows up in PLoS1. This is intriguing and certainly adds one more piece of the puzzle but I am not sure why it so earth-shattering. We already know that we have hominins in the Levant that pass, in most ways, for modern humans and are dated to between 90 and 110 000 B.P. We also have the Herto remains at 140-160 000, which are also mostly modern. A glance at the map shows that the gap between the Horn of Africa and the Arabian peninsula is very narrow here and it would not have been a problem to navigate the waters at this point. This just represents another migration route of many. The authors of the paper call the assemblage that was discovered a Nubian variant of the “Middle Stone Age,” which tracks as a post-Acheulean industry and is present in various forms in Africa from about 300 000 years B.P. down to around 40 000 or so. Here is the map from the article:

As you can see, there is Nubian in both Arabia and in the Nile valley. Interestingly, when you get to the Levantine peninsula, you run into “modern” humans creating Levantine Mousterian, another Middle Palaeolithic industry, which means they had contact with the Neandertals who were escaping the cold to come south during the early Würm glaciation. It is during the Early Würm/Late Würm interglacial period that the early moderns get the bright idea to head north, out of the Levant.